To have it run the number consistently, you need to be able to adjust it to track and atmospheric conditions. 2 tenths isn't much. I would probably use weight instead of fiddling with the throttle linkage, short shifting, etc. That way the engine/converter/gear change responds the same everytime. Put a weight box in it and go test. Make a pass, throw in 25#, throw in 50#, throw in 100#, and see what it does. Get a baseline, keep track of the air - you should know how the air effects the car - and know how much every 10# speed up or slow down the car.